Track lighting is used in many commercial establishments, especially retail establishments. Track lighting has the advantage of allowing sources of light to be repositioned periodically to highlight different areas or subjects. It is desirable to provide informative signs as part of a track lighting system in a commercial establishment. By mounting an internally illuminated sign on a track, the sign may be utilized to deliver a message at a specific location. The sign may be periodically relocated, along with sources of light. The message displayed by the sign should be readily changed without the use of extensive tools or equipment to be economically effective. Furthermore, the change should be capable of being made by a relatively unskilled individual.